Cloud computing is all the rage.
"It's become the phrase du jour," says Gartner senior analyst Ben
Pring, echoing many of his peers. The problem is that (as with Web 2.0)
everyone seems to have a different definition.
As a metaphor for the Internet,
"the cloud" is a familiar cliché, but when combined with
"computing," the meaning gets bigger and fuzzier. Some analysts and
vendors define cloud computing narrowly as an updated version of utility
computing: basically virtual
servers available over the Internet. Others go very broad, arguing anything
you consume outside the firewall is "in the cloud," including
conventional outsourcing.
Cloud computing comes into focus
only when you think about what IT always needs: a way to increase capacity or
add capabilities on the fly without investing in new infrastructure, training
new personnel, or licensing new software. Cloud computing encompasses any
subscription-based or pay-per-use service that, in real time over the Internet,
extends IT's existing capabilities.
Cloud computing is at an early
stage, with a motley crew of providers large and small delivering a slew of
cloud-based services, from full-blown applications to storage services to spam
filtering. Yes, utility-style infrastructure providers are part of the mix, but
so are SaaS
(software as a service) providers such as Salesforce.com. Today, for the
most part, IT must plug into cloud-based services individually, but cloud
computing aggregators and integrators are already emerging.
InfoWorld talked to dozens of
vendors, analysts, and IT customers to tease out the various components of
cloud computing. Based on those discussions, here's a rough breakdown of what
cloud computing is all about:
1. SaaS
This type of cloud computing delivers
a single application through the browser to thousands of customers using a
multitenant architecture. On the customer side, it means no upfront investment
in servers or software licensing; on the provider side, with just one app to
maintain, costs are low compared to conventional hosting. Salesforce.com is by
far the best-known example among enterprise applications, but SaaS is also
common for HR apps and has even worked its way up the food chain to ERP, with
players such as Workday. And who could have predicted the sudden rise of SaaS "desktop"
applications, such as Google Apps and Zoho Office?
2. Utility computing
The idea is not new, but this form
of cloud computing is getting new life from Amazon.com, Sun, IBM, and others
who now offer storage and virtual servers that IT can access on demand. Early
enterprise adopters mainly use utility computing for supplemental, non-mission-critical
needs, but one day, they may replace parts of the datacenter. Other providers
offer solutions that help IT create virtual datacenters from commodity servers,
such as 3Tera's AppLogic and Cohesive Flexible Technologies' Elastic Server on
Demand. Liquid Computing's LiquidQ offers similar capabilities, enabling IT to
stitch together memory, I/O, storage, and computational capacity as a
virtualized resource pool available over the network.
3. Web services in the cloud
Closely related to SaaS, Web service providers offer APIs that enable
developers to exploit functionality over the Internet, rather than delivering
full-blown applications. They range from providers offering discrete business
services -- such as Strike Iron and Xignite -- to the full range of APIs
offered by Google Maps, ADP payroll processing, the U.S. Postal Service,
Bloomberg, and even conventional credit card processing services.
4. Platform as a service
Another SaaS variation, this form of cloud computing delivers development environments
as a service. You build your own applications that run on the provider's
infrastructure and are delivered to your users via the Internet from the
provider's servers. Like Legos, these services are constrained by the vendor's
design and capabilities, so you don't get complete freedom, but you do get
predictability and pre-integration. Prime examples include Salesforce.com's
Force.com,
Coghead
and the new
Google
App Engine. For extremely lightweight development, cloud-based
mashup platforms
abound, such as
Yahoo
Pipes or Dapper.net.
5. MSP (managed service providers)
One of the oldest forms of cloud computing, a managed service is basically
an application exposed to IT rather than to end-users, such as a virus scanning
service for e-mail or an application monitoring service (which Mercury, among
others, provides). Managed security services delivered by SecureWorks, IBM, and
Verizon fall into this category, as do such cloud-based anti-spam services as
Postini, recently acquired by Google. Other offerings include desktop
management services, such as those offered by CenterBeam or Everdream.
6. Service commerce platforms
A hybrid of SaaS and MSP, this cloud computing service offers a service hub
that users interact with. They're most common in trading environments, such as
expense management systems that allow users to order travel or secretarial
services from a common platform that then coordinates the service delivery and
pricing within the specifications set by the user. Think of it as an automated
service bureau. Well-known examples include Rearden Commerce and Ariba.
7. Internet integration
The integration of cloud-based services is in its early days. OpSource,
which mainly concerns itself with serving SaaS providers, recently introduced
the OpSource Services Bus, which employs in-the-cloud integration technology from
a little startup called Boomi. SaaS provider Workday recently acquired another
player in this space, CapeClear, an ESB (enterprise service bus) provider that
was edging toward b-to-b integration. Way ahead of its time, Grand Central --
which wanted to be a universal "bus in the cloud" to connect SaaS
providers and provide integrated solutions to customers -- flamed out in 2005.
Today, with such cloud-based interconnection seldom in evidence, cloud
computing might be more accurately described as "sky computing," with
many isolated clouds of services which IT customers must plug into
individually. On the other hand, as virtualization and SOA permeate the
enterprise, the idea of loosely coupled services running on an agile, scalable
infrastructure should eventually make every enterprise a node in the cloud.
It's a long-running trend with a far-out horizon. But among big metatrends,
cloud computing is the hardest one to argue with in the long term.